A polarizing plate is, for example, an optically functional film that is applied to devices such as liquid crystal display devices (LCDs), etc.
The polarizing plate includes a polarizer that is a functional sheet which can extract light that oscillates in one direction from incident light that oscillates in all directions, and may also include triacetyl cellulose (TAC)-based protective films which are generally attached to both surfaces of the polarizer by means of an adhesive or pressure-sensitive adhesive.
However, a typical TAC-based protective film has problems in that it is expensive, and difficult to manufacture. Therefore, an acrylic protective film, and the like have been used as the protective film to replace the TAC-based protective film. Also, since the TAC-based protective film has moisture absorbency, a water-based adhesive such as a polyvinyl alcohol adhesive may be used as the TAC-based protective film. Owing to low moisture absorbency, however, the acrylic protective film is generally attached to the polarizer using a UV-curable adhesive instead of the water-based adhesive. In this case, however, the acrylic protective film shows poor adhesive strength to the polarizer, and thus primer coating is performed on one surface or both surfaces of the acrylic protective film so as to solve the problems.